1. Field of the Invention
The present invention relates to an electrical device cooling structure in a vehicle, comprising: an electrical device which includes a battery for driving a motor for traveling, a DC/DC converter and a motor driving inverter, the electrical device being disposed below a floor behind a seat, and cooled by cooling air.
2. Description of the Related Art
Japanese Patent Application Laid-open No. 2003-45392 discloses a device in which a power supply device including a battery that drives a motor for traveling of an automobile is mounted in a trunk room behind a rear seat, and the battery is cooled by cooling air supplied by a forced air fan provided integrally with the power supply device.
Japanese Patent Application Laid-open No. 2005-153827 discloses a device in which a capacitor including a battery that drives a motor for traveling of an automobile, a DC/DC converter, a motor driving inverter, a cooling fan, and the like is disposed below a rear seat, and the battery, the DC/DC converter, and the motor driving inverter are cooled by cooling air sucked by a cooling fan.
Japanese Patent Application Laid-open No. 2003-45392 discloses that the battery of the power supply device is cooled by the cooling air supplied by the forced air fan, but does not disclose cooling of a DC/DC converter and a motor driving inverter included in the power supply device.
In Japanese Patent Application Laid-open No. 2005-153827, the battery, the DC/DC converter, the motor driving inverter, and the cooling fan are disposed in series in a vehicle width direction, and the battery, the DC/DC converter, and the motor driving inverter are sequentially cooled by the cooling air sucked by the cooling fan.
In this device, the temperature of the cooling air is gradually increased by heat exchange during the cooling of the battery, the DC/DC converter, and the motor driving inverter. Therefore, even if the battery on an upstream side can be sufficiently cooled, there is a possibility that the motor driving inverter on a downstream side is not sufficiently cooled. Also, because the battery, the DC/DC converter, the motor driving inverter and the cooling fan are disposed in series, the size of the power supply device is increased to impose a limitation in mounting the power supply device on the vehicle. Further, because resistance is increased in the passage of the cooling air, a large and high-performance cooling fan is disadvantageously needed.